It says: a successful bruteforce of your unique unlock code would give you your permanent unlock, no ultrasn0w needed

Since I am only interested in unlock not jailbreak, does this mean the new unlock tool will make my iPhone 4 unlocked just like factory unlock, and I can upgrade to official software, become none-jailbroken but still remain unlocked?

No, this means that Ultrasn0w will work like it always has--a soft unlock. The Dev Team can only produce a soft unlock. A bruteforce unlock is what Apple uses in countries like Austrailia and France which require phones to be unlocked. A bruteforce unlocked iPhone will remain unlocked forever, an Ultrasn0w unlock will not.

It says: a successful bruteforce of your unique unlock code would give you your permanent unlock, no ultrasn0w needed

Since I am only interested in unlock not jailbreak, does this mean the new unlock tool will make my iPhone 4 unlocked just like factory unlock, and I can upgrade to official software, become none-jailbroken but still remain unlocked?

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No. Ultrasn0w on the iPhone4 simply allows you to dump out the "secrom" of the baseband which contains the hash of the NCK unlock code you need to enter to permanently unlock the unit.

However, to actually brute force the code based on this information is STILL a pretty insane effort (maybe a few months of computational power with a respectable CPU+GPU), so you can feel free to spend $500 on electricity or whatnot to give it a shot, but it's probably not the best use of your efforts.

The key point is that without access to the secrom, brute-forcing would be impossible. Ultrasn0w just makes it possible -- whether or not it's practical is a different story.

No. Ultrasn0w on the iPhone4 simply allows you to dump out the "secrom" of the baseband which contains the hash of the NCK unlock code you need to enter to permanently unlock the unit.

However, to actually brute force the code based on this information is STILL a pretty insane effort (maybe a few months of computational power with a respectable CPU+GPU), so you can feel free to spend $500 on electricity or whatnot to give it a shot, but it's probably not the best use of your efforts.

The key point is that without access to the secrom, brute-forcing would be impossible. Ultrasn0w just makes it possible -- whether or not it's practical is a different story.

Do you know any details of what a factory unlock actually is? In other words, do they use software or is some type of hardware change that allows this?

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The factory unlock is done during activation. AT&T sends an encrypted unlock token which is unique to your device. I understand that with this seczone dump it is theoretically possible to find that token by brute force. You could then spoof the activation server and permanently unlock your phone.

The factory unlock is done during activation. AT&T sends an encrypted unlock token which is unique to your device. I understand that with this seczone dump it is theoretically possible to find that token by brute force. You could then spoof the activation server and permanently unlock your phone.

I recall someone a year or so again collecting NCK codes and sec zone dumps from people officially unlocking the phone. He was trying to find the algorithm to generate the NCK codes, but needless to say he didn't get anywhere. As already mentioned it's a huge computational effort. If someone were to find the algorithm though, it would mean every iPhone in the world could be easily unlocked. Only a dream though

I recall someone a year or so again collecting NCK codes and sec zone dumps from people officially unlocking the phone. He was trying to find the algorithm to generate the NCK codes, but needless to say he didn't get anywhere. As already mentioned it's a huge computational effort. If someone were to find the algorithm though, it would mean every iPhone in the world could be easily unlocked. Only a dream though

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MuscleNerd has said that it doesn't appear to be algorithmic. Apple must keep a database of every phone's unlock code on its activation server.

The factory unlock is done during activation. AT&T sends an encrypted unlock token which is unique to your device. I understand that with this seczone dump it is theoretically possible to find that token by brute force. You could then spoof the activation server and permanently unlock your phone.

Click to expand...

Close, but it has very little to do with AT&T or any other carrier. They just tell Apple when one of their customers' iPhones needs unlocking.

Apple keeps a database of these unlocked iPhone IDs that is checked by iTunes as required. If your phone's on the list, iTunes makes sure it's unlocked.

When Apple sells an unlocked iPhone, in the UK for example, its ID gets added to the list. However, once an iPhone has been assigned to a carrier, such as AT&T, only that organisation is authorised to add that phone to the database.

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